| 1 | /* |
| 2 | * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved. |
| 3 | * |
| 4 | * This code is derived from software contributed to The DragonFly Project |
| 5 | * by Jeffrey M. Hsu. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 16 | * contributors may be used to endorse or promote products derived |
| 17 | * from this software without specific, prior written permission. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 21 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 22 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 23 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 24 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 25 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 26 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 27 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 28 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 29 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 30 | * SUCH DAMAGE. |
| 31 | */ |
| 32 | |
| 33 | /* |
| 34 | * Copyright (c) 1982, 1986, 1988, 1993 |
| 35 | * The Regents of the University of California. All rights reserved. |
| 36 | * |
| 37 | * Redistribution and use in source and binary forms, with or without |
| 38 | * modification, are permitted provided that the following conditions |
| 39 | * are met: |
| 40 | * 1. Redistributions of source code must retain the above copyright |
| 41 | * notice, this list of conditions and the following disclaimer. |
| 42 | * 2. Redistributions in binary form must reproduce the above copyright |
| 43 | * notice, this list of conditions and the following disclaimer in the |
| 44 | * documentation and/or other materials provided with the distribution. |
| 45 | * 3. All advertising materials mentioning features or use of this software |
| 46 | * must display the following acknowledgement: |
| 47 | * This product includes software developed by the University of |
| 48 | * California, Berkeley and its contributors. |
| 49 | * 4. Neither the name of the University nor the names of its contributors |
| 50 | * may be used to endorse or promote products derived from this software |
| 51 | * without specific prior written permission. |
| 52 | * |
| 53 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 54 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 55 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 56 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 57 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 58 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 59 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 60 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 61 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 62 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 63 | * SUCH DAMAGE. |
| 64 | * |
| 65 | * @(#)if_ether.c 8.1 (Berkeley) 6/10/93 |
| 66 | * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $ |
| 67 | * $DragonFly: src/sys/netinet/if_ether.c,v 1.59 2008/11/22 11:03:35 sephe Exp $ |
| 68 | */ |
| 69 | |
| 70 | /* |
| 71 | * Ethernet address resolution protocol. |
| 72 | * TODO: |
| 73 | * add "inuse/lock" bit (or ref. count) along with valid bit |
| 74 | */ |
| 75 | |
| 76 | #include "opt_inet.h" |
| 77 | #include "opt_carp.h" |
| 78 | |
| 79 | #include <sys/param.h> |
| 80 | #include <sys/kernel.h> |
| 81 | #include <sys/queue.h> |
| 82 | #include <sys/sysctl.h> |
| 83 | #include <sys/systm.h> |
| 84 | #include <sys/mbuf.h> |
| 85 | #include <sys/malloc.h> |
| 86 | #include <sys/socket.h> |
| 87 | #include <sys/syslog.h> |
| 88 | #include <sys/lock.h> |
| 89 | |
| 90 | #include <net/if.h> |
| 91 | #include <net/if_dl.h> |
| 92 | #include <net/if_types.h> |
| 93 | #include <net/route.h> |
| 94 | #include <net/netisr.h> |
| 95 | #include <net/if_llc.h> |
| 96 | |
| 97 | #include <netinet/in.h> |
| 98 | #include <netinet/in_var.h> |
| 99 | #include <netinet/if_ether.h> |
| 100 | |
| 101 | #include <sys/thread2.h> |
| 102 | #include <sys/msgport2.h> |
| 103 | #include <net/netmsg2.h> |
| 104 | #include <sys/mplock2.h> |
| 105 | |
| 106 | #ifdef CARP |
| 107 | #include <netinet/ip_carp.h> |
| 108 | #endif |
| 109 | |
| 110 | #define SIN(s) ((struct sockaddr_in *)s) |
| 111 | #define SDL(s) ((struct sockaddr_dl *)s) |
| 112 | |
| 113 | SYSCTL_DECL(_net_link_ether); |
| 114 | SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, ""); |
| 115 | |
| 116 | /* timer values */ |
| 117 | static int arpt_prune = (5*60*1); /* walk list every 5 minutes */ |
| 118 | static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */ |
| 119 | static int arpt_down = 20; /* once declared down, don't send for 20 sec */ |
| 120 | |
| 121 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW, |
| 122 | &arpt_prune, 0, ""); |
| 123 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW, |
| 124 | &arpt_keep, 0, ""); |
| 125 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW, |
| 126 | &arpt_down, 0, ""); |
| 127 | |
| 128 | #define rt_expire rt_rmx.rmx_expire |
| 129 | |
| 130 | struct llinfo_arp { |
| 131 | LIST_ENTRY(llinfo_arp) la_le; |
| 132 | struct rtentry *la_rt; |
| 133 | struct mbuf *la_hold; /* last packet until resolved/timeout */ |
| 134 | struct lwkt_port *la_msgport; /* last packet's msgport */ |
| 135 | u_short la_preempt; /* countdown for pre-expiry arps */ |
| 136 | u_short la_asked; /* #times we QUERIED following expiration */ |
| 137 | }; |
| 138 | |
| 139 | static LIST_HEAD(, llinfo_arp) llinfo_arp_list[MAXCPU]; |
| 140 | |
| 141 | static int arp_maxtries = 5; |
| 142 | static int useloopback = 1; /* use loopback interface for local traffic */ |
| 143 | static int arp_proxyall = 0; |
| 144 | static int arp_refresh = 60; /* refresh arp cache ~60 (not impl yet) */ |
| 145 | static int arp_restricted_match = 0; |
| 146 | |
| 147 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW, |
| 148 | &arp_maxtries, 0, "ARP resolution attempts before returning error"); |
| 149 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW, |
| 150 | &useloopback, 0, "Use the loopback interface for local traffic"); |
| 151 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW, |
| 152 | &arp_proxyall, 0, "Enable proxy ARP for all suitable requests"); |
| 153 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, restricted_match, CTLFLAG_RW, |
| 154 | &arp_restricted_match, 0, "Only match against the sender"); |
| 155 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, refresh, CTLFLAG_RW, |
| 156 | &arp_refresh, 0, "Preemptively refresh the ARP"); |
| 157 | |
| 158 | static void arp_rtrequest(int, struct rtentry *, struct rt_addrinfo *); |
| 159 | static void arprequest(struct ifnet *, const struct in_addr *, |
| 160 | const struct in_addr *, const u_char *); |
| 161 | static void arprequest_async(struct ifnet *, const struct in_addr *, |
| 162 | const struct in_addr *, const u_char *); |
| 163 | static void arpintr(netmsg_t msg); |
| 164 | static void arptfree(struct llinfo_arp *); |
| 165 | static void arptimer(void *); |
| 166 | static struct llinfo_arp * |
| 167 | arplookup(in_addr_t, boolean_t, boolean_t, boolean_t); |
| 168 | #ifdef INET |
| 169 | static void in_arpinput(struct mbuf *); |
| 170 | #endif |
| 171 | |
| 172 | static struct callout arptimer_ch[MAXCPU]; |
| 173 | |
| 174 | /* |
| 175 | * Timeout routine. Age arp_tab entries periodically. |
| 176 | */ |
| 177 | /* ARGSUSED */ |
| 178 | static void |
| 179 | arptimer(void *ignored_arg) |
| 180 | { |
| 181 | struct llinfo_arp *la, *nla; |
| 182 | |
| 183 | crit_enter(); |
| 184 | LIST_FOREACH_MUTABLE(la, &llinfo_arp_list[mycpuid], la_le, nla) { |
| 185 | if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_second) |
| 186 | arptfree(la); |
| 187 | } |
| 188 | callout_reset(&arptimer_ch[mycpuid], arpt_prune * hz, arptimer, NULL); |
| 189 | crit_exit(); |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * Parallel to llc_rtrequest. |
| 194 | * |
| 195 | * Called after a route is successfully added to the tree to fix-up the |
| 196 | * route and initiate arp operations if required. |
| 197 | */ |
| 198 | static void |
| 199 | arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info) |
| 200 | { |
| 201 | struct sockaddr *gate = rt->rt_gateway; |
| 202 | struct llinfo_arp *la = rt->rt_llinfo; |
| 203 | |
| 204 | struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK }; |
| 205 | static boolean_t arpinit_done[MAXCPU]; |
| 206 | |
| 207 | if (!arpinit_done[mycpuid]) { |
| 208 | arpinit_done[mycpuid] = TRUE; |
| 209 | callout_init(&arptimer_ch[mycpuid]); |
| 210 | callout_reset(&arptimer_ch[mycpuid], hz, arptimer, NULL); |
| 211 | } |
| 212 | if (rt->rt_flags & RTF_GATEWAY) |
| 213 | return; |
| 214 | |
| 215 | switch (req) { |
| 216 | case RTM_ADD: |
| 217 | /* |
| 218 | * XXX: If this is a manually added route to interface |
| 219 | * such as older version of routed or gated might provide, |
| 220 | * restore cloning bit. |
| 221 | */ |
| 222 | if (!(rt->rt_flags & RTF_HOST) && |
| 223 | SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) |
| 224 | rt->rt_flags |= RTF_CLONING; |
| 225 | if (rt->rt_flags & RTF_CLONING) { |
| 226 | /* |
| 227 | * Case 1: This route should come from a route to iface. |
| 228 | */ |
| 229 | rt_setgate(rt, rt_key(rt), |
| 230 | (struct sockaddr *)&null_sdl, |
| 231 | RTL_DONTREPORT); |
| 232 | gate = rt->rt_gateway; |
| 233 | SDL(gate)->sdl_type = rt->rt_ifp->if_type; |
| 234 | SDL(gate)->sdl_index = rt->rt_ifp->if_index; |
| 235 | rt->rt_expire = time_second; |
| 236 | break; |
| 237 | } |
| 238 | /* Announce a new entry if requested. */ |
| 239 | if (rt->rt_flags & RTF_ANNOUNCE) { |
| 240 | arprequest_async(rt->rt_ifp, |
| 241 | &SIN(rt_key(rt))->sin_addr, |
| 242 | &SIN(rt_key(rt))->sin_addr, |
| 243 | LLADDR(SDL(gate))); |
| 244 | } |
| 245 | /*FALLTHROUGH*/ |
| 246 | case RTM_RESOLVE: |
| 247 | if (gate->sa_family != AF_LINK || |
| 248 | gate->sa_len < sizeof(struct sockaddr_dl)) { |
| 249 | log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n"); |
| 250 | break; |
| 251 | } |
| 252 | SDL(gate)->sdl_type = rt->rt_ifp->if_type; |
| 253 | SDL(gate)->sdl_index = rt->rt_ifp->if_index; |
| 254 | if (la != NULL) |
| 255 | break; /* This happens on a route change */ |
| 256 | /* |
| 257 | * Case 2: This route may come from cloning, or a manual route |
| 258 | * add with a LL address. |
| 259 | */ |
| 260 | R_Malloc(la, struct llinfo_arp *, sizeof *la); |
| 261 | rt->rt_llinfo = la; |
| 262 | if (la == NULL) { |
| 263 | log(LOG_DEBUG, "arp_rtrequest: malloc failed\n"); |
| 264 | break; |
| 265 | } |
| 266 | bzero(la, sizeof *la); |
| 267 | la->la_rt = rt; |
| 268 | rt->rt_flags |= RTF_LLINFO; |
| 269 | LIST_INSERT_HEAD(&llinfo_arp_list[mycpuid], la, la_le); |
| 270 | |
| 271 | #ifdef INET |
| 272 | /* |
| 273 | * This keeps the multicast addresses from showing up |
| 274 | * in `arp -a' listings as unresolved. It's not actually |
| 275 | * functional. Then the same for broadcast. |
| 276 | */ |
| 277 | if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) { |
| 278 | ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr, |
| 279 | LLADDR(SDL(gate))); |
| 280 | SDL(gate)->sdl_alen = 6; |
| 281 | rt->rt_expire = 0; |
| 282 | } |
| 283 | if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) { |
| 284 | memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr, |
| 285 | rt->rt_ifp->if_addrlen); |
| 286 | SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen; |
| 287 | rt->rt_expire = 0; |
| 288 | } |
| 289 | #endif |
| 290 | |
| 291 | /* |
| 292 | * This fixes up the routing interface for local addresses. |
| 293 | * The route is adjusted to point at lo0 and the expiration |
| 294 | * timer is disabled. |
| 295 | * |
| 296 | * NOTE: This prevents locally targetted traffic from going |
| 297 | * out the hardware interface, which is inefficient |
| 298 | * and might not work if the hardware cannot listen |
| 299 | * to its own transmitted packets. Setting |
| 300 | * net.link.ether.inet.useloopback to 0 will force |
| 301 | * packets for local addresses out the hardware (and |
| 302 | * it is expected to receive its own packet). |
| 303 | * |
| 304 | * XXX We should just be able to test RTF_LOCAL here instead |
| 305 | * of having to compare IPs. |
| 306 | */ |
| 307 | if (SIN(rt_key(rt))->sin_addr.s_addr == |
| 308 | (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) { |
| 309 | rt->rt_expire = 0; |
| 310 | bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)), |
| 311 | SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen); |
| 312 | if (useloopback) |
| 313 | rt->rt_ifp = loif; |
| 314 | } |
| 315 | break; |
| 316 | |
| 317 | case RTM_DELETE: |
| 318 | if (la == NULL) |
| 319 | break; |
| 320 | LIST_REMOVE(la, la_le); |
| 321 | rt->rt_llinfo = NULL; |
| 322 | rt->rt_flags &= ~RTF_LLINFO; |
| 323 | if (la->la_hold != NULL) |
| 324 | m_freem(la->la_hold); |
| 325 | Free(la); |
| 326 | break; |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | static struct mbuf * |
| 331 | arpreq_alloc(struct ifnet *ifp, const struct in_addr *sip, |
| 332 | const struct in_addr *tip, const u_char *enaddr) |
| 333 | { |
| 334 | struct mbuf *m; |
| 335 | struct arphdr *ah; |
| 336 | u_short ar_hrd; |
| 337 | |
| 338 | if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL) |
| 339 | return NULL; |
| 340 | m->m_pkthdr.rcvif = NULL; |
| 341 | |
| 342 | switch (ifp->if_type) { |
| 343 | case IFT_ETHER: |
| 344 | /* |
| 345 | * This may not be correct for types not explicitly |
| 346 | * listed, but this is our best guess |
| 347 | */ |
| 348 | default: |
| 349 | ar_hrd = htons(ARPHRD_ETHER); |
| 350 | |
| 351 | m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr)); |
| 352 | m->m_pkthdr.len = m->m_len; |
| 353 | MH_ALIGN(m, m->m_len); |
| 354 | |
| 355 | ah = mtod(m, struct arphdr *); |
| 356 | break; |
| 357 | } |
| 358 | |
| 359 | ah->ar_hrd = ar_hrd; |
| 360 | ah->ar_pro = htons(ETHERTYPE_IP); |
| 361 | ah->ar_hln = ifp->if_addrlen; /* hardware address length */ |
| 362 | ah->ar_pln = sizeof(struct in_addr); /* protocol address length */ |
| 363 | ah->ar_op = htons(ARPOP_REQUEST); |
| 364 | memcpy(ar_sha(ah), enaddr, ah->ar_hln); |
| 365 | memset(ar_tha(ah), 0, ah->ar_hln); |
| 366 | memcpy(ar_spa(ah), sip, ah->ar_pln); |
| 367 | memcpy(ar_tpa(ah), tip, ah->ar_pln); |
| 368 | |
| 369 | return m; |
| 370 | } |
| 371 | |
| 372 | static void |
| 373 | arpreq_send(struct ifnet *ifp, struct mbuf *m) |
| 374 | { |
| 375 | struct sockaddr sa; |
| 376 | struct ether_header *eh; |
| 377 | |
| 378 | switch (ifp->if_type) { |
| 379 | case IFT_ETHER: |
| 380 | /* |
| 381 | * This may not be correct for types not explicitly |
| 382 | * listed, but this is our best guess |
| 383 | */ |
| 384 | default: |
| 385 | eh = (struct ether_header *)sa.sa_data; |
| 386 | /* if_output() will not swap */ |
| 387 | eh->ether_type = htons(ETHERTYPE_ARP); |
| 388 | memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen); |
| 389 | break; |
| 390 | } |
| 391 | |
| 392 | sa.sa_family = AF_UNSPEC; |
| 393 | sa.sa_len = sizeof(sa); |
| 394 | ifp->if_output(ifp, m, &sa, NULL); |
| 395 | } |
| 396 | |
| 397 | static void |
| 398 | arpreq_send_handler(netmsg_t msg) |
| 399 | { |
| 400 | struct mbuf *m = msg->packet.nm_packet; |
| 401 | struct ifnet *ifp = msg->lmsg.u.ms_resultp; |
| 402 | |
| 403 | arpreq_send(ifp, m); |
| 404 | /* nmsg was embedded in the mbuf, do not reply! */ |
| 405 | } |
| 406 | |
| 407 | /* |
| 408 | * Broadcast an ARP request. Caller specifies: |
| 409 | * - arp header source ip address |
| 410 | * - arp header target ip address |
| 411 | * - arp header source ethernet address |
| 412 | * |
| 413 | * NOTE: Caller MUST NOT hold ifp's serializer |
| 414 | */ |
| 415 | static void |
| 416 | arprequest(struct ifnet *ifp, const struct in_addr *sip, |
| 417 | const struct in_addr *tip, const u_char *enaddr) |
| 418 | { |
| 419 | struct mbuf *m; |
| 420 | |
| 421 | if (enaddr == NULL) { |
| 422 | if (ifp->if_bridge) { |
| 423 | enaddr = IF_LLADDR(ether_bridge_interface(ifp)); |
| 424 | } else { |
| 425 | enaddr = IF_LLADDR(ifp); |
| 426 | } |
| 427 | } |
| 428 | |
| 429 | m = arpreq_alloc(ifp, sip, tip, enaddr); |
| 430 | if (m == NULL) |
| 431 | return; |
| 432 | arpreq_send(ifp, m); |
| 433 | } |
| 434 | |
| 435 | /* |
| 436 | * Same as arprequest(), except: |
| 437 | * - Caller is allowed to hold ifp's serializer |
| 438 | * - Network output is done in protocol thead |
| 439 | */ |
| 440 | static void |
| 441 | arprequest_async(struct ifnet *ifp, const struct in_addr *sip, |
| 442 | const struct in_addr *tip, const u_char *enaddr) |
| 443 | { |
| 444 | struct mbuf *m; |
| 445 | struct netmsg_packet *pmsg; |
| 446 | |
| 447 | if (enaddr == NULL) { |
| 448 | if (ifp->if_bridge) { |
| 449 | enaddr = IF_LLADDR(ether_bridge_interface(ifp)); |
| 450 | } else { |
| 451 | enaddr = IF_LLADDR(ifp); |
| 452 | } |
| 453 | } |
| 454 | m = arpreq_alloc(ifp, sip, tip, enaddr); |
| 455 | if (m == NULL) |
| 456 | return; |
| 457 | |
| 458 | pmsg = &m->m_hdr.mh_netmsg; |
| 459 | netmsg_init(&pmsg->base, NULL, &netisr_apanic_rport, |
| 460 | 0, arpreq_send_handler); |
| 461 | pmsg->nm_packet = m; |
| 462 | pmsg->base.lmsg.u.ms_resultp = ifp; |
| 463 | |
| 464 | lwkt_sendmsg(cpu_portfn(mycpuid), &pmsg->base.lmsg); |
| 465 | } |
| 466 | |
| 467 | /* |
| 468 | * Resolve an IP address into an ethernet address. If success, |
| 469 | * desten is filled in. If there is no entry in arptab, |
| 470 | * set one up and broadcast a request for the IP address. |
| 471 | * Hold onto this mbuf and resend it once the address |
| 472 | * is finally resolved. A return value of 1 indicates |
| 473 | * that desten has been filled in and the packet should be sent |
| 474 | * normally; a 0 return indicates that the packet has been |
| 475 | * taken over here, either now or for later transmission. |
| 476 | */ |
| 477 | int |
| 478 | arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m, |
| 479 | struct sockaddr *dst, u_char *desten) |
| 480 | { |
| 481 | struct rtentry *rt; |
| 482 | struct llinfo_arp *la = NULL; |
| 483 | struct sockaddr_dl *sdl; |
| 484 | |
| 485 | if (m->m_flags & M_BCAST) { /* broadcast */ |
| 486 | memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen); |
| 487 | return (1); |
| 488 | } |
| 489 | if (m->m_flags & M_MCAST) {/* multicast */ |
| 490 | ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten); |
| 491 | return (1); |
| 492 | } |
| 493 | if (rt0 != NULL) { |
| 494 | if (rt_llroute(dst, rt0, &rt) != 0) { |
| 495 | m_freem(m); |
| 496 | return 0; |
| 497 | } |
| 498 | la = rt->rt_llinfo; |
| 499 | } |
| 500 | if (la == NULL) { |
| 501 | la = arplookup(SIN(dst)->sin_addr.s_addr, |
| 502 | TRUE, RTL_REPORTMSG, FALSE); |
| 503 | if (la != NULL) |
| 504 | rt = la->la_rt; |
| 505 | } |
| 506 | if (la == NULL || rt == NULL) { |
| 507 | log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n", |
| 508 | inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ", |
| 509 | rt ? "rt" : ""); |
| 510 | m_freem(m); |
| 511 | return (0); |
| 512 | } |
| 513 | sdl = SDL(rt->rt_gateway); |
| 514 | /* |
| 515 | * Check the address family and length is valid, the address |
| 516 | * is resolved; otherwise, try to resolve. |
| 517 | */ |
| 518 | if ((rt->rt_expire == 0 || rt->rt_expire > time_second) && |
| 519 | sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) { |
| 520 | /* |
| 521 | * If entry has an expiry time and it is approaching, |
| 522 | * see if we need to send an ARP request within this |
| 523 | * arpt_down interval. |
| 524 | */ |
| 525 | if ((rt->rt_expire != 0) && |
| 526 | (time_second + la->la_preempt > rt->rt_expire)) { |
| 527 | arprequest(ifp, |
| 528 | &SIN(rt->rt_ifa->ifa_addr)->sin_addr, |
| 529 | &SIN(dst)->sin_addr, |
| 530 | NULL); |
| 531 | la->la_preempt--; |
| 532 | } |
| 533 | |
| 534 | bcopy(LLADDR(sdl), desten, sdl->sdl_alen); |
| 535 | return 1; |
| 536 | } |
| 537 | /* |
| 538 | * If ARP is disabled or static on this interface, stop. |
| 539 | * XXX |
| 540 | * Probably should not allocate empty llinfo struct if we are |
| 541 | * not going to be sending out an arp request. |
| 542 | */ |
| 543 | if (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) { |
| 544 | m_freem(m); |
| 545 | return (0); |
| 546 | } |
| 547 | /* |
| 548 | * There is an arptab entry, but no ethernet address |
| 549 | * response yet. Replace the held mbuf with this |
| 550 | * latest one. |
| 551 | */ |
| 552 | if (la->la_hold != NULL) |
| 553 | m_freem(la->la_hold); |
| 554 | la->la_hold = m; |
| 555 | la->la_msgport = cur_netport(); |
| 556 | if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) { |
| 557 | rt->rt_flags &= ~RTF_REJECT; |
| 558 | if (la->la_asked == 0 || rt->rt_expire != time_second) { |
| 559 | rt->rt_expire = time_second; |
| 560 | if (la->la_asked++ < arp_maxtries) { |
| 561 | arprequest(ifp, |
| 562 | &SIN(rt->rt_ifa->ifa_addr)->sin_addr, |
| 563 | &SIN(dst)->sin_addr, |
| 564 | NULL); |
| 565 | } else { |
| 566 | rt->rt_flags |= RTF_REJECT; |
| 567 | rt->rt_expire += arpt_down; |
| 568 | la->la_asked = 0; |
| 569 | la->la_preempt = arp_maxtries; |
| 570 | } |
| 571 | } |
| 572 | } |
| 573 | return (0); |
| 574 | } |
| 575 | |
| 576 | /* |
| 577 | * Common length and type checks are done here, |
| 578 | * then the protocol-specific routine is called. |
| 579 | */ |
| 580 | static void |
| 581 | arpintr(netmsg_t msg) |
| 582 | { |
| 583 | struct mbuf *m = msg->packet.nm_packet; |
| 584 | struct arphdr *ar; |
| 585 | u_short ar_hrd; |
| 586 | |
| 587 | if (m->m_len < sizeof(struct arphdr) && |
| 588 | (m = m_pullup(m, sizeof(struct arphdr))) == NULL) { |
| 589 | log(LOG_ERR, "arp: runt packet -- m_pullup failed\n"); |
| 590 | return; |
| 591 | } |
| 592 | ar = mtod(m, struct arphdr *); |
| 593 | |
| 594 | ar_hrd = ntohs(ar->ar_hrd); |
| 595 | if (ar_hrd != ARPHRD_ETHER && ar_hrd != ARPHRD_IEEE802) { |
| 596 | log(LOG_ERR, "arp: unknown hardware address format (0x%2D)\n", |
| 597 | (unsigned char *)&ar->ar_hrd, ""); |
| 598 | m_freem(m); |
| 599 | return; |
| 600 | } |
| 601 | |
| 602 | if (m->m_pkthdr.len < arphdr_len(ar)) { |
| 603 | if ((m = m_pullup(m, arphdr_len(ar))) == NULL) { |
| 604 | log(LOG_ERR, "arp: runt packet\n"); |
| 605 | return; |
| 606 | } |
| 607 | ar = mtod(m, struct arphdr *); |
| 608 | } |
| 609 | |
| 610 | switch (ntohs(ar->ar_pro)) { |
| 611 | #ifdef INET |
| 612 | case ETHERTYPE_IP: |
| 613 | in_arpinput(m); |
| 614 | return; |
| 615 | #endif |
| 616 | } |
| 617 | m_freem(m); |
| 618 | /* msg was embedded in the mbuf, do not reply! */ |
| 619 | } |
| 620 | |
| 621 | #ifdef INET |
| 622 | /* |
| 623 | * ARP for Internet protocols on 10 Mb/s Ethernet. |
| 624 | * Algorithm is that given in RFC 826. |
| 625 | * In addition, a sanity check is performed on the sender |
| 626 | * protocol address, to catch impersonators. |
| 627 | * We no longer handle negotiations for use of trailer protocol: |
| 628 | * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent |
| 629 | * along with IP replies if we wanted trailers sent to us, |
| 630 | * and also sent them in response to IP replies. |
| 631 | * This allowed either end to announce the desire to receive |
| 632 | * trailer packets. |
| 633 | * We no longer reply to requests for ETHERTYPE_TRAIL protocol either, |
| 634 | * but formerly didn't normally send requests. |
| 635 | */ |
| 636 | |
| 637 | static int log_arp_wrong_iface = 1; |
| 638 | static int log_arp_movements = 1; |
| 639 | static int log_arp_permanent_modify = 1; |
| 640 | |
| 641 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW, |
| 642 | &log_arp_wrong_iface, 0, |
| 643 | "Log arp packets arriving on the wrong interface"); |
| 644 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW, |
| 645 | &log_arp_movements, 0, |
| 646 | "Log arp replies from MACs different than the one in the cache"); |
| 647 | SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW, |
| 648 | &log_arp_permanent_modify, 0, |
| 649 | "Log arp replies from MACs different than the one " |
| 650 | "in the permanent arp entry"); |
| 651 | |
| 652 | |
| 653 | static void |
| 654 | arp_hold_output(netmsg_t msg) |
| 655 | { |
| 656 | struct mbuf *m = msg->packet.nm_packet; |
| 657 | struct rtentry *rt; |
| 658 | struct ifnet *ifp; |
| 659 | |
| 660 | rt = msg->lmsg.u.ms_resultp; |
| 661 | ifp = m->m_pkthdr.rcvif; |
| 662 | m->m_pkthdr.rcvif = NULL; |
| 663 | |
| 664 | ifp->if_output(ifp, m, rt_key(rt), rt); |
| 665 | |
| 666 | /* Drop the reference count bumped by the sender */ |
| 667 | RTFREE(rt); |
| 668 | |
| 669 | /* nmsg was embedded in the mbuf, do not reply! */ |
| 670 | } |
| 671 | |
| 672 | static void |
| 673 | arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create, |
| 674 | boolean_t generate_report, boolean_t dologging) |
| 675 | { |
| 676 | struct arphdr *ah = mtod(m, struct arphdr *); |
| 677 | struct ifnet *ifp = m->m_pkthdr.rcvif; |
| 678 | struct llinfo_arp *la; |
| 679 | struct sockaddr_dl *sdl; |
| 680 | struct rtentry *rt; |
| 681 | |
| 682 | la = arplookup(saddr, create, generate_report, FALSE); |
| 683 | if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) { |
| 684 | struct in_addr isaddr = { saddr }; |
| 685 | |
| 686 | /* |
| 687 | * Normally arps coming in on the wrong interface are ignored, |
| 688 | * but if we are bridging and the two interfaces belong to |
| 689 | * the same bridge, or one is a member of the bridge which |
| 690 | * is the other, then it isn't an error. |
| 691 | */ |
| 692 | if (rt->rt_ifp != ifp) { |
| 693 | /* |
| 694 | * (1) ifp and rt_ifp both members of same bridge |
| 695 | * (2) rt_ifp member of bridge ifp |
| 696 | * (3) ifp member of bridge rt_ifp |
| 697 | * |
| 698 | * Always replace rt_ifp with the bridge ifc. |
| 699 | */ |
| 700 | struct ifnet *nifp; |
| 701 | |
| 702 | if (ifp->if_bridge && |
| 703 | rt->rt_ifp->if_bridge == ifp->if_bridge) { |
| 704 | nifp = ether_bridge_interface(ifp); |
| 705 | } else if (rt->rt_ifp->if_bridge && |
| 706 | ether_bridge_interface(rt->rt_ifp) == ifp) { |
| 707 | nifp = ifp; |
| 708 | } else if (ifp->if_bridge && |
| 709 | ether_bridge_interface(ifp) == rt->rt_ifp) { |
| 710 | nifp = rt->rt_ifp; |
| 711 | } else { |
| 712 | nifp = NULL; |
| 713 | } |
| 714 | |
| 715 | if ((log_arp_wrong_iface == 1 && nifp == NULL) || |
| 716 | log_arp_wrong_iface == 2) { |
| 717 | log(LOG_ERR, |
| 718 | "arp: %s is on %s " |
| 719 | "but got reply from %*D on %s\n", |
| 720 | inet_ntoa(isaddr), |
| 721 | rt->rt_ifp->if_xname, |
| 722 | ifp->if_addrlen, (u_char *)ar_sha(ah), ":", |
| 723 | ifp->if_xname); |
| 724 | } |
| 725 | if (nifp == NULL) |
| 726 | return; |
| 727 | |
| 728 | /* |
| 729 | * nifp is our man! Replace rt_ifp and adjust |
| 730 | * the sdl. |
| 731 | */ |
| 732 | ifp = rt->rt_ifp = nifp; |
| 733 | sdl->sdl_type = ifp->if_type; |
| 734 | sdl->sdl_index = ifp->if_index; |
| 735 | } |
| 736 | if (sdl->sdl_alen && |
| 737 | bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) { |
| 738 | if (rt->rt_expire != 0) { |
| 739 | if (dologging && log_arp_movements) { |
| 740 | log(LOG_INFO, |
| 741 | "arp: %s moved from %*D to %*D on %s\n", |
| 742 | inet_ntoa(isaddr), |
| 743 | ifp->if_addrlen, (u_char *)LLADDR(sdl), |
| 744 | ":", ifp->if_addrlen, |
| 745 | (u_char *)ar_sha(ah), ":", |
| 746 | ifp->if_xname); |
| 747 | } |
| 748 | } else { |
| 749 | if (dologging && log_arp_permanent_modify) { |
| 750 | log(LOG_ERR, |
| 751 | "arp: %*D attempts to modify " |
| 752 | "permanent entry for %s on %s\n", |
| 753 | ifp->if_addrlen, (u_char *)ar_sha(ah), |
| 754 | ":", inet_ntoa(isaddr), ifp->if_xname); |
| 755 | } |
| 756 | return; |
| 757 | } |
| 758 | } |
| 759 | /* |
| 760 | * sanity check for the address length. |
| 761 | * XXX this does not work for protocols with variable address |
| 762 | * length. -is |
| 763 | */ |
| 764 | if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln) { |
| 765 | log(LOG_WARNING, |
| 766 | "arp from %*D: new addr len %d, was %d", |
| 767 | ifp->if_addrlen, (u_char *) ar_sha(ah), ":", |
| 768 | ah->ar_hln, sdl->sdl_alen); |
| 769 | } |
| 770 | if (ifp->if_addrlen != ah->ar_hln) { |
| 771 | if (dologging) { |
| 772 | log(LOG_WARNING, |
| 773 | "arp from %*D: addr len: new %d, i/f %d " |
| 774 | "(ignored)", |
| 775 | ifp->if_addrlen, (u_char *) ar_sha(ah), ":", |
| 776 | ah->ar_hln, ifp->if_addrlen); |
| 777 | } |
| 778 | return; |
| 779 | } |
| 780 | memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln); |
| 781 | if (rt->rt_expire != 0) { |
| 782 | rt->rt_expire = time_second + arpt_keep; |
| 783 | } |
| 784 | rt->rt_flags &= ~RTF_REJECT; |
| 785 | la->la_asked = 0; |
| 786 | la->la_preempt = arp_maxtries; |
| 787 | |
| 788 | /* |
| 789 | * This particular cpu might have been holding an mbuf |
| 790 | * pending ARP resolution. If so, transmit the mbuf now. |
| 791 | */ |
| 792 | if (la->la_hold != NULL) { |
| 793 | struct mbuf *m = la->la_hold; |
| 794 | struct lwkt_port *port = la->la_msgport; |
| 795 | struct netmsg_packet *pmsg; |
| 796 | |
| 797 | la->la_hold = NULL; |
| 798 | la->la_msgport = NULL; |
| 799 | |
| 800 | m_adj(m, sizeof(struct ether_header)); |
| 801 | |
| 802 | /* |
| 803 | * Make sure that this rtentry will not be freed |
| 804 | * before the packet is processed on the target |
| 805 | * msgport. The reference count will be dropped |
| 806 | * in the handler associated with this packet. |
| 807 | */ |
| 808 | rt->rt_refcnt++; |
| 809 | |
| 810 | pmsg = &m->m_hdr.mh_netmsg; |
| 811 | netmsg_init(&pmsg->base, NULL, |
| 812 | &netisr_apanic_rport, |
| 813 | MSGF_PRIORITY, arp_hold_output); |
| 814 | pmsg->nm_packet = m; |
| 815 | |
| 816 | /* Record necessary information */ |
| 817 | m->m_pkthdr.rcvif = ifp; |
| 818 | pmsg->base.lmsg.u.ms_resultp = rt; |
| 819 | |
| 820 | lwkt_sendmsg(port, &pmsg->base.lmsg); |
| 821 | } |
| 822 | } |
| 823 | } |
| 824 | |
| 825 | #ifdef SMP |
| 826 | |
| 827 | struct netmsg_arp_update { |
| 828 | struct netmsg_base base; |
| 829 | struct mbuf *m; |
| 830 | in_addr_t saddr; |
| 831 | boolean_t create; |
| 832 | }; |
| 833 | |
| 834 | static void arp_update_msghandler(netmsg_t msg); |
| 835 | |
| 836 | #endif |
| 837 | |
| 838 | /* |
| 839 | * Called from arpintr() - this routine is run from a single cpu. |
| 840 | */ |
| 841 | static void |
| 842 | in_arpinput(struct mbuf *m) |
| 843 | { |
| 844 | struct arphdr *ah; |
| 845 | struct ifnet *ifp = m->m_pkthdr.rcvif; |
| 846 | struct ether_header *eh; |
| 847 | struct rtentry *rt; |
| 848 | struct ifaddr_container *ifac; |
| 849 | struct in_ifaddr_container *iac; |
| 850 | struct in_ifaddr *ia = NULL; |
| 851 | struct sockaddr sa; |
| 852 | struct in_addr isaddr, itaddr, myaddr; |
| 853 | #ifdef SMP |
| 854 | struct netmsg_arp_update msg; |
| 855 | #endif |
| 856 | uint8_t *enaddr = NULL; |
| 857 | int op; |
| 858 | int req_len; |
| 859 | |
| 860 | req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr)); |
| 861 | if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) { |
| 862 | log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n"); |
| 863 | return; |
| 864 | } |
| 865 | |
| 866 | ah = mtod(m, struct arphdr *); |
| 867 | op = ntohs(ah->ar_op); |
| 868 | memcpy(&isaddr, ar_spa(ah), sizeof isaddr); |
| 869 | memcpy(&itaddr, ar_tpa(ah), sizeof itaddr); |
| 870 | |
| 871 | myaddr.s_addr = INADDR_ANY; |
| 872 | #ifdef CARP |
| 873 | if (ifp->if_carp != NULL) { |
| 874 | get_mplock(); |
| 875 | if (ifp->if_carp != NULL && |
| 876 | carp_iamatch(ifp->if_carp, &itaddr, &isaddr, &enaddr)) { |
| 877 | rel_mplock(); |
| 878 | myaddr = itaddr; |
| 879 | goto match; |
| 880 | } |
| 881 | rel_mplock(); |
| 882 | } |
| 883 | #endif |
| 884 | |
| 885 | /* |
| 886 | * Check both target and sender IP addresses: |
| 887 | * |
| 888 | * If we receive the packet on the interface owning the address, |
| 889 | * then accept the address. |
| 890 | * |
| 891 | * For a bridge, we accept the address if the receive interface and |
| 892 | * the interface owning the address are on the same bridge, and |
| 893 | * use the bridge MAC as the is-at response. The bridge will be |
| 894 | * responsible for handling the packet. |
| 895 | * |
| 896 | * (1) Check target IP against our local IPs |
| 897 | */ |
| 898 | LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) { |
| 899 | ia = iac->ia; |
| 900 | |
| 901 | /* Skip all ia's which don't match */ |
| 902 | if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr) |
| 903 | continue; |
| 904 | #ifdef CARP |
| 905 | if (ia->ia_ifp->if_type == IFT_CARP) |
| 906 | continue; |
| 907 | #endif |
| 908 | if (ifp->if_bridge && ia->ia_ifp && |
| 909 | ifp->if_bridge == ia->ia_ifp->if_bridge) { |
| 910 | ifp = ether_bridge_interface(ifp); |
| 911 | goto match; |
| 912 | } |
| 913 | if (ia->ia_ifp && ia->ia_ifp->if_bridge && |
| 914 | ether_bridge_interface(ia->ia_ifp) == ifp) { |
| 915 | goto match; |
| 916 | } |
| 917 | if (ifp->if_bridge && ether_bridge_interface(ifp) == |
| 918 | ia->ia_ifp) { |
| 919 | goto match; |
| 920 | } |
| 921 | if (ia->ia_ifp == ifp) |
| 922 | goto match; |
| 923 | |
| 924 | } |
| 925 | |
| 926 | /* |
| 927 | * (2) Check sender IP against our local IPs |
| 928 | */ |
| 929 | LIST_FOREACH(iac, INADDR_HASH(isaddr.s_addr), ia_hash) { |
| 930 | ia = iac->ia; |
| 931 | |
| 932 | /* Skip all ia's which don't match */ |
| 933 | if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr) |
| 934 | continue; |
| 935 | #ifdef CARP |
| 936 | if (ia->ia_ifp->if_type == IFT_CARP) |
| 937 | continue; |
| 938 | #endif |
| 939 | if (ifp->if_bridge && ia->ia_ifp && |
| 940 | ifp->if_bridge == ia->ia_ifp->if_bridge) { |
| 941 | ifp = ether_bridge_interface(ifp); |
| 942 | goto match; |
| 943 | } |
| 944 | if (ia->ia_ifp && ia->ia_ifp->if_bridge && |
| 945 | ether_bridge_interface(ia->ia_ifp) == ifp) { |
| 946 | goto match; |
| 947 | } |
| 948 | if (ifp->if_bridge && ether_bridge_interface(ifp) == |
| 949 | ia->ia_ifp) { |
| 950 | goto match; |
| 951 | } |
| 952 | |
| 953 | if (ia->ia_ifp == ifp) |
| 954 | goto match; |
| 955 | } |
| 956 | |
| 957 | /* |
| 958 | * No match, use the first inet address on the receive interface |
| 959 | * as a dummy address for the rest of the function. |
| 960 | */ |
| 961 | TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { |
| 962 | struct ifaddr *ifa = ifac->ifa; |
| 963 | |
| 964 | if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) { |
| 965 | ia = ifatoia(ifa); |
| 966 | goto match; |
| 967 | } |
| 968 | } |
| 969 | |
| 970 | /* |
| 971 | * If we got here, we didn't find any suitable interface, |
| 972 | * so drop the packet. |
| 973 | */ |
| 974 | m_freem(m); |
| 975 | return; |
| 976 | |
| 977 | match: |
| 978 | if (!enaddr) |
| 979 | enaddr = (uint8_t *)IF_LLADDR(ifp); |
| 980 | if (myaddr.s_addr == INADDR_ANY) |
| 981 | myaddr = ia->ia_addr.sin_addr; |
| 982 | if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) { |
| 983 | m_freem(m); /* it's from me, ignore it. */ |
| 984 | return; |
| 985 | } |
| 986 | if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) { |
| 987 | log(LOG_ERR, |
| 988 | "arp: link address is broadcast for IP address %s!\n", |
| 989 | inet_ntoa(isaddr)); |
| 990 | m_freem(m); |
| 991 | return; |
| 992 | } |
| 993 | if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) { |
| 994 | log(LOG_ERR, |
| 995 | "arp: %*D is using my IP address %s!\n", |
| 996 | ifp->if_addrlen, (u_char *)ar_sha(ah), ":", |
| 997 | inet_ntoa(isaddr)); |
| 998 | itaddr = myaddr; |
| 999 | goto reply; |
| 1000 | } |
| 1001 | if (ifp->if_flags & IFF_STATICARP) |
| 1002 | goto reply; |
| 1003 | |
| 1004 | /* |
| 1005 | * When arp_restricted_match is true and the ARP response is not |
| 1006 | * specifically targetted to me, ignore it. Otherwise the entry |
| 1007 | * timeout may be updated for an old MAC. |
| 1008 | */ |
| 1009 | if (arp_restricted_match && itaddr.s_addr != myaddr.s_addr) { |
| 1010 | m_freem(m); |
| 1011 | return; |
| 1012 | } |
| 1013 | |
| 1014 | #ifdef SMP |
| 1015 | netmsg_init(&msg.base, NULL, &curthread->td_msgport, |
| 1016 | 0, arp_update_msghandler); |
| 1017 | msg.m = m; |
| 1018 | msg.saddr = isaddr.s_addr; |
| 1019 | msg.create = (itaddr.s_addr == myaddr.s_addr); |
| 1020 | lwkt_domsg(rtable_portfn(0), &msg.base.lmsg, 0); |
| 1021 | #else |
| 1022 | arp_update_oncpu(m, isaddr.s_addr, (itaddr.s_addr == myaddr.s_addr), |
| 1023 | RTL_REPORTMSG, TRUE); |
| 1024 | #endif |
| 1025 | reply: |
| 1026 | if (op != ARPOP_REQUEST) { |
| 1027 | m_freem(m); |
| 1028 | return; |
| 1029 | } |
| 1030 | if (itaddr.s_addr == myaddr.s_addr) { |
| 1031 | /* I am the target */ |
| 1032 | memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); |
| 1033 | memcpy(ar_sha(ah), enaddr, ah->ar_hln); |
| 1034 | } else { |
| 1035 | struct llinfo_arp *la; |
| 1036 | |
| 1037 | la = arplookup(itaddr.s_addr, FALSE, RTL_DONTREPORT, SIN_PROXY); |
| 1038 | if (la == NULL) { |
| 1039 | struct sockaddr_in sin; |
| 1040 | |
| 1041 | if (!arp_proxyall) { |
| 1042 | m_freem(m); |
| 1043 | return; |
| 1044 | } |
| 1045 | |
| 1046 | bzero(&sin, sizeof sin); |
| 1047 | sin.sin_family = AF_INET; |
| 1048 | sin.sin_len = sizeof sin; |
| 1049 | sin.sin_addr = itaddr; |
| 1050 | |
| 1051 | rt = rtpurelookup((struct sockaddr *)&sin); |
| 1052 | if (rt == NULL) { |
| 1053 | m_freem(m); |
| 1054 | return; |
| 1055 | } |
| 1056 | --rt->rt_refcnt; |
| 1057 | /* |
| 1058 | * Don't send proxies for nodes on the same interface |
| 1059 | * as this one came out of, or we'll get into a fight |
| 1060 | * over who claims what Ether address. |
| 1061 | */ |
| 1062 | if (rt->rt_ifp == ifp) { |
| 1063 | m_freem(m); |
| 1064 | return; |
| 1065 | } |
| 1066 | memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); |
| 1067 | memcpy(ar_sha(ah), enaddr, ah->ar_hln); |
| 1068 | #ifdef DEBUG_PROXY |
| 1069 | kprintf("arp: proxying for %s\n", inet_ntoa(itaddr)); |
| 1070 | #endif |
| 1071 | } else { |
| 1072 | struct sockaddr_dl *sdl; |
| 1073 | |
| 1074 | rt = la->la_rt; |
| 1075 | memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); |
| 1076 | sdl = SDL(rt->rt_gateway); |
| 1077 | memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln); |
| 1078 | } |
| 1079 | } |
| 1080 | |
| 1081 | memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln); |
| 1082 | memcpy(ar_spa(ah), &itaddr, ah->ar_pln); |
| 1083 | ah->ar_op = htons(ARPOP_REPLY); |
| 1084 | ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */ |
| 1085 | switch (ifp->if_type) { |
| 1086 | case IFT_ETHER: |
| 1087 | /* |
| 1088 | * May not be correct for types not explictly |
| 1089 | * listed, but it is our best guess. |
| 1090 | */ |
| 1091 | default: |
| 1092 | eh = (struct ether_header *)sa.sa_data; |
| 1093 | memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost); |
| 1094 | eh->ether_type = htons(ETHERTYPE_ARP); |
| 1095 | break; |
| 1096 | } |
| 1097 | sa.sa_family = AF_UNSPEC; |
| 1098 | sa.sa_len = sizeof sa; |
| 1099 | ifp->if_output(ifp, m, &sa, NULL); |
| 1100 | } |
| 1101 | |
| 1102 | #ifdef SMP |
| 1103 | |
| 1104 | static void |
| 1105 | arp_update_msghandler(netmsg_t msg) |
| 1106 | { |
| 1107 | struct netmsg_arp_update *rmsg = (struct netmsg_arp_update *)msg; |
| 1108 | int nextcpu; |
| 1109 | |
| 1110 | /* |
| 1111 | * This message handler will be called on all of the CPUs, |
| 1112 | * however, we only need to generate rtmsg on CPU0. |
| 1113 | */ |
| 1114 | arp_update_oncpu(rmsg->m, rmsg->saddr, rmsg->create, |
| 1115 | mycpuid == 0 ? RTL_REPORTMSG : RTL_DONTREPORT, |
| 1116 | mycpuid == 0); |
| 1117 | |
| 1118 | nextcpu = mycpuid + 1; |
| 1119 | if (nextcpu < ncpus) |
| 1120 | lwkt_forwardmsg(rtable_portfn(nextcpu), &rmsg->base.lmsg); |
| 1121 | else |
| 1122 | lwkt_replymsg(&rmsg->base.lmsg, 0); |
| 1123 | } |
| 1124 | |
| 1125 | #endif /* SMP */ |
| 1126 | |
| 1127 | #endif /* INET */ |
| 1128 | |
| 1129 | /* |
| 1130 | * Free an arp entry. If the arp entry is actively referenced or represents |
| 1131 | * a static entry we only clear it back to an unresolved state, otherwise |
| 1132 | * we destroy the entry entirely. |
| 1133 | * |
| 1134 | * Note that static entries are created when route add ... -interface is used |
| 1135 | * to create an interface route to a (direct) destination. |
| 1136 | */ |
| 1137 | static void |
| 1138 | arptfree(struct llinfo_arp *la) |
| 1139 | { |
| 1140 | struct rtentry *rt = la->la_rt; |
| 1141 | struct sockaddr_dl *sdl; |
| 1142 | |
| 1143 | if (rt == NULL) |
| 1144 | panic("arptfree"); |
| 1145 | sdl = SDL(rt->rt_gateway); |
| 1146 | if (sdl != NULL && |
| 1147 | ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) || |
| 1148 | (rt->rt_flags & RTF_STATIC))) { |
| 1149 | sdl->sdl_alen = 0; |
| 1150 | la->la_preempt = la->la_asked = 0; |
| 1151 | rt->rt_flags &= ~RTF_REJECT; |
| 1152 | return; |
| 1153 | } |
| 1154 | rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL); |
| 1155 | } |
| 1156 | |
| 1157 | /* |
| 1158 | * Lookup or enter a new address in arptab. |
| 1159 | */ |
| 1160 | static struct llinfo_arp * |
| 1161 | arplookup(in_addr_t addr, boolean_t create, boolean_t generate_report, |
| 1162 | boolean_t proxy) |
| 1163 | { |
| 1164 | struct rtentry *rt; |
| 1165 | struct sockaddr_inarp sin = { sizeof sin, AF_INET }; |
| 1166 | const char *why = NULL; |
| 1167 | |
| 1168 | sin.sin_addr.s_addr = addr; |
| 1169 | sin.sin_other = proxy ? SIN_PROXY : 0; |
| 1170 | if (create) { |
| 1171 | rt = _rtlookup((struct sockaddr *)&sin, |
| 1172 | generate_report, RTL_DOCLONE); |
| 1173 | } else { |
| 1174 | rt = rtpurelookup((struct sockaddr *)&sin); |
| 1175 | } |
| 1176 | if (rt == NULL) |
| 1177 | return (NULL); |
| 1178 | rt->rt_refcnt--; |
| 1179 | |
| 1180 | if (rt->rt_flags & RTF_GATEWAY) |
| 1181 | why = "host is not on local network"; |
| 1182 | else if (!(rt->rt_flags & RTF_LLINFO)) |
| 1183 | why = "could not allocate llinfo"; |
| 1184 | else if (rt->rt_gateway->sa_family != AF_LINK) |
| 1185 | why = "gateway route is not ours"; |
| 1186 | |
| 1187 | if (why) { |
| 1188 | if (create) { |
| 1189 | log(LOG_DEBUG, "arplookup %s failed: %s\n", |
| 1190 | inet_ntoa(sin.sin_addr), why); |
| 1191 | } |
| 1192 | if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) { |
| 1193 | /* No references to this route. Purge it. */ |
| 1194 | rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, |
| 1195 | rt_mask(rt), rt->rt_flags, NULL); |
| 1196 | } |
| 1197 | return (NULL); |
| 1198 | } |
| 1199 | return (rt->rt_llinfo); |
| 1200 | } |
| 1201 | |
| 1202 | void |
| 1203 | arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa) |
| 1204 | { |
| 1205 | if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY) { |
| 1206 | arprequest_async(ifp, &IA_SIN(ifa)->sin_addr, |
| 1207 | &IA_SIN(ifa)->sin_addr, NULL); |
| 1208 | } |
| 1209 | ifa->ifa_rtrequest = arp_rtrequest; |
| 1210 | ifa->ifa_flags |= RTF_CLONING; |
| 1211 | } |
| 1212 | |
| 1213 | void |
| 1214 | arp_iainit(struct ifnet *ifp, const struct in_addr *addr, const u_char *enaddr) |
| 1215 | { |
| 1216 | if (addr->s_addr != INADDR_ANY) |
| 1217 | arprequest_async(ifp, addr, addr, enaddr); |
| 1218 | } |
| 1219 | |
| 1220 | static void |
| 1221 | arp_init(void) |
| 1222 | { |
| 1223 | int cpu; |
| 1224 | |
| 1225 | for (cpu = 0; cpu < ncpus2; cpu++) |
| 1226 | LIST_INIT(&llinfo_arp_list[cpu]); |
| 1227 | |
| 1228 | netisr_register(NETISR_ARP, arpintr, NULL); |
| 1229 | } |
| 1230 | |
| 1231 | SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0); |